The IQ2 violet laser diode module from Power Technology Inc. emits 20 mW at 405 ±10 nm, according to the company. It uses anamorphic correcting prisms to produce a circularized, astigmatism-free beam and has a precision current source and a PID temperature controller for applications requiring stability of power and wavelength. The module, which can operate in CW mode or with analog or TTL modulation, is 7.52 in. long and 1.5 in. in diameter and has an adjustable focus, and glass and optional beam-expanding optics. Applications include microscopy, spectroscopy, interferometry and laser-induced fluorescence.